DRM C5

I'm having a new engine built using a LS6 short block(got at great price). A friend suggested I should have the offset grind the crankshaft which could increase the stroke from 3.62 to maybe 3.75. By doing so, I imagine that I would need longer or shorter connecting rods? Would I also need new pistons?

I appreciate everyone's advice.

J-Rod

Yes, you will need new pistons if you offset grind the crank. To gain some stroke, you might look at using a used NASCAR rod (about $400 for a set of good Carillos), and have the rod journal turned down to a Accura rod bearing (1.888) size journal. But, the simple answer is yes you can offset grind. Of course with some of the more affordable cranks coming out you may wish to look at the cost benefit analysis of an offset ground stock crank vs an Eagle (which is on sale right now...)

Pro Stock John

iTrader: (34)

Also check with Valvegod@aol.com he had one 3.778 stroke billet crank lying around, new never used for like $1000. One of the cranks that GM used to mess around with 360ci stuff.

taqwache

i got my stock crank off set ground locally to a 2.00" rod journal and 3.71 stroke for $150. the guy that did it said that it was the exact same process then a SBC crank which he has done plenty of. now he charges $200. the pistons will have to be custom but with my motor, i can just use a 350 SBC piston for a 6.0" rod. it ended up beeing the same compression height of 1.26" but i got a custom set anyways since i was going to spray it. if you got money, then just buy a stroker crank from eagle. in my case, i dont really like spending money in my car so i always find a cheap way out to go faster .

in the end, i ended up getting 380 cubes out of a 6.0L block for cheap. you also have to add the fact that with a smaller rod journal diamater, you lose rotating mass from the crank, bearings, and rods. and since the bearings have less surface area on them, you will have less friction then a standard 2.10 rod journal bearing. this all adds to that little bit more HP you can get out of it.

FASTONE

If you cut the rod journals down .100 you can only gain .050 in stroke,if you take off .100 from the side closest to mains you only move the center of the rod journal over ..050. .050 gain is it! On a 4 inch bore you"ll gain about 5.0 cu in.

taqwache

Fastone, since the rod journal goes up and down, it will gain the whole .100". .050 on the up stroke and .050 on the down stroke. so total cubes gained was 10.

racer7088

NO you'll gain .050 of crank arm or .100 total in stroke since you double that!

racer7088

OOps someone already posted that.

FASTONE

You are right ,my bad SO YOU CAN GAIN 10 OR 11 CI?SORRY!!

taqwache

yup, i ended up with a 380 instead of a 370 with all the other advantages.

J-Rod

Again, you can go to 1.888 instead of 2.00 and find some really good deals on rods, and pick up a bit more stroke....